#define _CRT_SECURE_NO_WARNINGS 1

#include <stdio.h>
#include <stdlib.h>

int my_atoi(char* p)
{
	int len = strlen(p);
	int sum = 0;
	for (int n = 0; n < len; n++)
	{
		sum *= 10;
		sum += p[n] - '0';
	}
	return sum;
}
int main()
{
	char arr[256] = { 0 };
	scanf("%s", arr);
	int i = my_atoi(arr);
	printf("i = %d\n", i);
	return 0;
}